Effect of chemicals, heat, and histopathologic processing on high-infectivity hamster-adapted scrapie virus.
High-titered (greater than 10(10) LD50 [50% lethal dose[/g) preparations of scrapie virus-infected hamster brain were subjected to inactivation by various chemicals, autoclaving, and histopathologic processing. Sodium hypochlorite, which reduced infectivity by approximately 4 log LD50/g of brain (99.99%), was somewhat superior to sodium metaperiodate and clearly superior to chlorine dioxide, Lysol (National Laboratories, Montvale, N.J.), iodine, potassium permanganate, and hydrogen peroxide. Most inactivation occurred within 15-30 min of exposure to a chemical, and little if any additional inactivation occurred after 1 hr. Brains processed for histopathologic examination (formalin fixation followed by dehydration in methanol, clearing in chloroform, and embedding in paraffin) retained greater than or equal to 6.8 log LD50/g of the infectivity present in unprocessed control tissues (9.6 log LD50/g). One hour in an autoclave at 121 C reduced the titer of scrapie virus by approximately 7.5 log LD50/g of brain but left 2.5 log LD50/g of residual infectivity. A combination of exposure to chemicals and autoclaving may be necessary to sterilize high-titered scrapie virus-infected tissue.
D000818:Animals; D001921:Brain / Q000382:microbiology*; D006224:Cricetinae; D004202:Disinfectants / Q000494:pharmacology; D006652:Histological Techniques; D006358:Hot Temperature; D066298:In Vitro Techniques; D007700:Kinetics; D008647:Mesocricetus; D011328:Prions / Q000187:drug effects / Q000302:isolation & purification / Q000472:pathogenicity*
D004202:Disinfectants; D011328:Prions